circuitpython/py/vm.c

283 lines
7.9 KiB
C

#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "misc.h"
#include "machine.h"
#include "runtime.h"
#include "vm.h"
#define DECODE_UINT do { unum = *ip++; if (unum > 127) { unum = ((unum & 0x3f) << 8) | (*ip++); } } while (0)
#define DECODE_QSTR do { qstr = *ip++; if (qstr > 127) { qstr = ((qstr & 0x3f) << 8) | (*ip++); } } while (0)
#define PUSH(val) *--sp = (val)
#define POP() (*sp++)
// args are in reverse order in array
py_obj_t py_execute_byte_code(const byte *code, uint len, const py_obj_t *args, uint n_args) {
const byte *ip = code;
py_obj_t stack[10];
py_obj_t *sp = &stack[10]; // stack grows down, sp points to top of stack
machine_uint_t unum;
machine_int_t snum;
qstr qstr;
py_obj_t obj1, obj2;
py_obj_t fast0 = NULL, fast1 = NULL, fast2 = NULL, fastn[4] = {NULL, NULL, NULL, NULL};
// init args
for (int i = 0; i < n_args; i++) {
if (i == 0) {
fast0 = args[n_args - 1];
} else if (i == 1) {
fast1 = args[n_args - 2];
} else if (i == 2) {
fast2 = args[n_args - 3];
} else {
assert(i - 3 < 4);
fastn[i - 3] = args[n_args - 1 - i];
}
}
// execute byte code
for (;;) {
int op = *ip++;
switch (op) {
case PYBC_LOAD_CONST_FALSE:
PUSH(py_const_false);
break;
case PYBC_LOAD_CONST_NONE:
PUSH(py_const_none);
break;
case PYBC_LOAD_CONST_TRUE:
PUSH(py_const_true);
break;
case PYBC_LOAD_CONST_SMALL_INT:
snum = ip[0] | (ip[1] << 8);
if (snum & 0x8000) {
snum |= ~0xffff;
}
ip += 2;
PUSH((py_obj_t)(snum << 1 | 1));
break;
case PYBC_LOAD_CONST_ID:
DECODE_QSTR;
PUSH(rt_load_const_str(qstr)); // TODO
break;
case PYBC_LOAD_CONST_STRING:
DECODE_QSTR;
PUSH(rt_load_const_str(qstr));
break;
case PYBC_LOAD_FAST_0:
PUSH(fast0);
break;
case PYBC_LOAD_FAST_1:
PUSH(fast1);
break;
case PYBC_LOAD_FAST_2:
PUSH(fast2);
break;
case PYBC_LOAD_FAST_N:
DECODE_UINT;
PUSH(fastn[unum - 3]);
break;
case PYBC_LOAD_NAME:
DECODE_QSTR;
PUSH(rt_load_name(qstr));
break;
case PYBC_LOAD_GLOBAL:
DECODE_QSTR;
PUSH(rt_load_global(qstr));
break;
case PYBC_LOAD_ATTR:
DECODE_QSTR;
*sp = rt_load_attr(*sp, qstr);
break;
case PYBC_LOAD_METHOD:
DECODE_QSTR;
sp -= 1;
rt_load_method(sp[1], qstr, sp);
break;
case PYBC_LOAD_BUILD_CLASS:
PUSH(rt_load_build_class());
break;
case PYBC_STORE_FAST_0:
fast0 = POP();
break;
case PYBC_STORE_FAST_1:
fast1 = POP();
break;
case PYBC_STORE_FAST_2:
fast2 = POP();
break;
case PYBC_STORE_FAST_N:
DECODE_UINT;
fastn[unum - 3] = POP();
break;
case PYBC_STORE_NAME:
DECODE_QSTR;
rt_store_name(qstr, POP());
break;
case PYBC_STORE_ATTR:
DECODE_QSTR;
rt_store_attr(sp[0], qstr, sp[1]);
sp += 2;
break;
case PYBC_STORE_SUBSCR:
rt_store_subscr(sp[1], sp[0], sp[2]);
sp += 3;
break;
case PYBC_DUP_TOP:
obj1 = *sp;
PUSH(obj1);
break;
case PYBC_DUP_TOP_TWO:
sp -= 2;
sp[0] = sp[2];
sp[1] = sp[3];
break;
case PYBC_POP_TOP:
++sp;
break;
case PYBC_ROT_THREE:
obj1 = sp[0];
sp[0] = sp[1];
sp[1] = sp[2];
sp[2] = obj1;
break;
case PYBC_JUMP:
DECODE_UINT;
ip = code + unum;
break;
case PYBC_POP_JUMP_IF_FALSE:
DECODE_UINT;
if (!rt_is_true(POP())) {
ip = code + unum;
}
break;
case PYBC_SETUP_LOOP:
DECODE_UINT;
break;
case PYBC_POP_BLOCK:
break;
case PYBC_BINARY_OP:
unum = *ip++;
obj2 = POP();
obj1 = *sp;
*sp = rt_binary_op(unum, obj1, obj2);
break;
case PYBC_COMPARE_OP:
unum = *ip++;
obj2 = POP();
obj1 = *sp;
*sp = rt_compare_op(unum, obj1, obj2);
break;
case PYBC_BUILD_LIST:
DECODE_UINT;
obj1 = rt_build_list(unum, sp);
sp += unum - 1;
*sp = obj1;
break;
case PYBC_BUILD_MAP:
DECODE_UINT;
PUSH(rt_build_map(unum));
break;
case PYBC_STORE_MAP:
sp += 2;
rt_store_map(sp[0], sp[-2], sp[-1]);
break;
case PYBC_BUILD_SET:
DECODE_UINT;
obj1 = rt_build_set(unum, sp);
sp += unum - 1;
*sp = obj1;
break;
case PYBC_MAKE_FUNCTION:
DECODE_UINT;
PUSH(rt_make_function_from_id(unum));
break;
case PYBC_CALL_FUNCTION:
DECODE_UINT;
assert((unum & 0xff00) == 0); // n_keyword
// switch on n_positional
if ((unum & 0xff) == 0) {
*sp = rt_call_function_0(*sp);
} else if ((unum & 0xff) == 1) {
obj1 = *sp++; // the single argument
*sp = rt_call_function_1(*sp, obj1);
} else if ((unum & 0xff) == 2) {
obj2 = *sp++; // the second argument
obj1 = *sp++; // the first argument
*sp = rt_call_function_2(*sp, obj1, obj2);
} else {
assert(0);
}
break;
case PYBC_CALL_METHOD:
DECODE_UINT;
assert((unum & 0xff00) == 0); // n_keyword
// switch on n_positional
if ((unum & 0xff) == 0) {
obj1 = *sp++; // the self object (or NULL)
*sp = rt_call_method_1(*sp, obj1);
} else if ((unum & 0xff) == 1) {
obj2 = *sp++; // the first argument
obj1 = *sp++; // the self object (or NULL)
*sp = rt_call_method_2(*sp, obj1, obj2);
} else {
unum = unum & 0xff;
obj1 = rt_call_method_n(unum, sp);
sp += unum + 1;
*sp = obj1;
}
break;
case PYBC_RETURN_VALUE:
return *sp;
default:
printf("code %p, offset %u, byte code 0x%02x not implemented\n", code, (uint)(ip - code), op);
assert(0);
return py_const_none;
}
}
}